Container fob assemblies to be



April 24, 1945. R L, BEASECKER v Re. 22,636

CONTAINER FOR ASSEMBLIES TO BE BONDED Original Filed Dec. 28, 1940Reissued Apr; 24, 1945 CONTAINER FOR ASSEMBLIES T BE BONDED Raymond L.Beasecker, Grand Rapids; Mich., as-

signor, by mesne assignments, to William B. Scarborough, Englewood, N.J., as trustee Original No. 2,307,985, dated January 12, 1943,

Serial No. 372,065, December 28, 1940. Application for reissue January12, 1944, Serial No.

6 Claims.

A common practice of bonding veneer assemblies to produce plywood,either in a flat, bent or molded form, is to lay an assembly upon asuitable die or support of the desired surface configuration and coverthe assembly with a rubber blanket which must :be fastened to the die orsupport to produce a sealed housing or container for the assembly. Thepackage thus created is placed in a closed chamber in which'is built upthe requisite uid pressure to accomplish the results desired; thepressure being accompanied by heating, where necessary, as, for example,by employing steam to provide both heat and pressure. Diiilculty hasheretofore been experienced in making the joints between the flexiblerubber member and the steel or other stiff die member sufficiently tightto prevent transfer of fluid between the interior of the housing orcontainer and the surrounding space. The common method of securing tightjoints is to lay steel bars on the rubber member, along the margins ofthe latter, and to apply clamps which, acting on one side against thebars and on the other side against the under face of the die or support,press the rubber tightly against the die or support. 'This method notonly requires the use o! clamping bars and numerous clamps, but muchtime is consumed in opening and closing the work containers, verygreatly reducing the amount of work that a single person can do.

The object, of the present invention is t0 produce a simple and novel-container or housing of the aforesaid type which requires no clampingbars or clamps to hold it closed and seal it but seals automaticallywhen the fluid pressure of the surrounding medium is substantiallygreater than that within the container or housing.

It has heretofore been attempted to cause the atmospheric pressure topress the marginal portions of the rubber member into sealing relationwith the die member upon connecting the space between the two to avacuum producing means and thus do away with mechanical fastenings. Thismethod has proved impracticable even when employing in the joints oilsor sealing compositions that do not set and form bonds between therubber members and the dies.

I have discovered that if the rubber member be constructed with a fairlydeep endless groove or channel into which the die or work-support may besprung and be a good iit, so that the part of the rubber immediatelyadjacent to the groove or channel constitutes a rim iitted upon the dieor work support, a joint may be obtained which is initiallysufl'iciently tight and which is Vcomes tighter and no objectionableleakage not likely to be disturbed in the ordinary handling of theapparatus while putting it into the pressure chamber. Then, ,when adifferential pressure between the interior and the exterior of thecontainer is brought about, with the greater pressure on theoutside, thejoint simply bethrough thel same in either direction can take place. Itis therefore a simple matter to unite the two sections of a container soas t0 enclose a piece of work, and it is perhaps even a simpleroperation to disconnect the two sections from each other. In addition tothe advantages heretofore mentioned, there is a further advantage inthat the damage to the rubber that is done under the old practice by theclamps and clamping bars is entirely avoided in my-'new construction.

The various features of novelty whereby my invention is characterizedwill hereinafter be pointed out with particularity in the claims; but.

` for a full understanding of my invention and of its objects andadvantages, reference may be had to the following detailed descriptiontaken in connection with the accompanying drawing, wherein:

Figures 1, 2 and 3 are respectively a top plan view, a bottom plan view,and a side view of a container or housing embodying the presentinvention, the same being shown in its closed condition, and the greaterpart between the ends thereof having been broken away,

Figure 4 is a section on line 4 4 of Figure 1, but on a larger scalethan that of Figure 1,

Figure 5 is a section on line 5 5 of Figure 1, on the same scale asFigure 4, and

Figure 6 is a view similar to Figure 4, showing a modification.

Referring to Figures 1 to 5; a die member is provided, comprising thedie or work support I, which is shown as being in the shape of a long,narrow, deep pan, the die l constituting the molding portion of the diemember. The die member includesV a wide flange 2 surrounding the same atthe top. The depth of the cavity within the molding portion I of the diemember is about that of a little stack A of veneers which are to bebonded together to produce a pieceof plywood almost as long and as wideas the cavity and of a thickness about equal to the depth of the cavity.The particular shape of the molding portion l of the die can be variedwithout departing from the scope of the present invention thevshapedepending entirely upon thc product which it is desired to make.The flange 2 comprises a marginal portion of the die disposed beyond theambit of the molding portion l. It

cooperates to seal the vmaterial A of the assembly against the diesurface, in a manner to be described hereinafter.

Cooperating with the die member is a cover preferably in the form of aflexible rubber blanket, preformed so that the body or molding portion 3thereof is companion to, and has sub- `stantially the Vsame length andwidth as, the

molding portion IV of the die. In addition, the blanket may be said,either to have a thickened marginal portion extending continuouslyaround the same and provided with a deep channel or groove cut into thethickened marginal portion from the inner edge, or to be hanged over soas to provide a deep continuous groove between the flange andthe'overlying boliy portion. At any rate, the resulting construction isa\at body member, the marginal portions of which have been turned overon one side to form an endless flange 4 spaced apart from the bodyportion a distance about equal to the thickness of the flange 2 of thedie. Thus there exists between the flange and the body portion of therubber section of the device a deep groove or channel 5 into which theflanges on the die may be' sprung. By properly proportioning the parts,the flanges or marginal portions 2 of the die can be made such a snug ntin 'the grooves orchannels 5 of the-cooperating rubber blanket memberthat the seal is just as satisfactory as is'the case where elaboratemechanical clamping devices are employed.

'I'he container is provided with a, suitable vent, indicated more or.less conventionally at 6, whereby the interior of vthe container may beplaced in conmiunication with the atmosphere outside of the pressurechamber (not shown), in which the treatment of the work is effected.Furthermore, this vent may be utilized to produce a partial vacuumwithin the container to bring about a preliminary sealing of the joint.

The structure of Figure 4 comprises the die member I, 2, and thecovering blanket 3, I, and 5, between which the material A of theassembly is enclosed. This constitutes a package'ready to be depositedin a chamber` of fluid under pressure. The pressure of the fluid in thechamber operates to mold lthe material A of the assembly to the contourof the molding portion I of the die, and operates to adhere the laminaeof the assembly together firmly. For fuller understanding of the moldingpractice, attention is directed veneer assembly A, 'the veneer assemblyB inv Fig. 6 has pressure exerted against it on all sides when thecontainer is subjected to pressure in the pressure chamber. In other`wordswlth this last construction, the Wallsof the body portion of therubber section, under external pressure,

are pressed into intimate contact, as shown in Fig. 6, not only with theface of the upper ply, but also with the edgefaces along the sides andthe ends of the plies.

As heretofore stated, the formsof containers or housings illustrated areintended simply for.

thel purpose of explaining the principles of my invention, since thestructures as a whole and the individual sections may take such shapesas the needs of the work to be done requiresyiust as is true in the,previous practice.

Upon placing a filled container in a pressure chamber and building up inthe latter a iiuid pressure in any suitable way, the effect is to causethe rubber to grip the margins of the ldie more strongly and thus bringabout atightening of the joint between the two sections; the greater thepressure, the tighter the joint. During this time the vent is, ofcourse, connected to the atmosphere surrounding the pressure chamber.

A typical practice for bending and bonding a plywood assembly under heatand pressure is as follows. After a package has been completed by layingthe assembly on the die and applying the cover, the vent is connected toa vacuum pump and about a twenty-seven inch vacuum is obtained. Hammerblows are then applied to the rubber blanket to jar the individuallayers of veneer into their proper positions. The vent is then closed bymeans of a suitable valve, not shown, and disconnected from the vacuumline. If the vacuum nowdoes not drop below about fifteen inches, theSeal is regarded as a good one. 'Ihe Vent is then connected to the tankline of the vacuum apparatus and the packageis inserted in the pressurechamber which is then filled with steam until the desired pressure tothe patent to Potchen et al., No. 2,308,453.

For the purposes of .the present invention, it is sufiicient to notethat the marginal portion of i siderably thicker than the rest of therubber member, as shown in Fig. 6, while still containing the deepchannel or groove 5 into which the marginal portions of the die memberfit; and it Amay be reenforced with fabric Ill, or otherwise.

It will be seen that although in the arrangement shown in Figs. l to 5the pressure is applied only at the top and to the bottom of the 'isattained. After the pressure against the exterior of the package hasbeen built up, the vent is disconnected from the vacuum line and` isplaced in communication with atmosphere outside of the pressure tank.Some minutes before the steam is shut ofi', the vent is again connectedto the vacuum line so as to insure against the formation of steampockets in the space in which the work is confined and the consequentrupturing of the rubber upon shutting oif the steam.- The steam is thenshut off, the vacuum broken, and the package removed from the pressurechamber. The container or housing is then opened and the bonded productremoved, whereupon it is ready to receive another assembly, so that theprocess just described may be repeated.

Therefore, while I have illustrated and described with particularityonly two simple forms of an apparatus embodying the present invention, Ido not desire to be limited to the exact structural details thusillustrated and described: but intend to cover all forms andarrangements which come within the definitions of my inventionconstituting the appended claims.

I claim:

i. 'I'he method of sealing an assembly for a multiple-ply structure in acontainer and effecting bonding under heat and pressure which consistsin inserting the assembly between a supporting member and a rubberycover having a portion extending continuously around the supportingmember and gripping the latter. producing a partial vacuum in the spacebetween the supporting member and the cover, enveloping the package inheated iluid under pressure, venting the aforesaid space to atmosphere,then creating a partial vacuum in said space and, finally. removing thepackage from the inuence of the heated fluid.

2. A two-piece separable container for a piece of work to be subjectedto the pressure of a fluid medium surrounding and in contact withthecontainer, which container is to be sealed by said pressure,consisting of a stiff supporting member for the work having a marginalportion extending continuously around the same, and a iiexible rubberycover member of a size to overlie a piece of work` on said supportingmember and rest on said marginal portion of the latter, said covermember having 'an inturned wide flange arouind its periphery defining anopening of smaller dimensions than said supporting member whereby saidflange extends inwardly past the edges of said supporting member andoverlies and engages said marginal portion when the cover is sprung inplace on the supporting member to enclose the work, that portion of thecover forming the marginal portion thereof at the base of the flangebeing sumciently thin to enable the pressure of said medium to force thematerial of the cover nrmly against both sides of the marginal portionof the supporting member and to enable removal of said .cover memberfrom said supporting member when the pressure is relieved.

3. A two-piece separable container for a piece of work to be subjectedto the pressure of the fluid medium surrounding and in contact with thecontainer. which is to be sealed by said pressure, consisting of a stiffsheet metal supporting member for the work and a preformed. exiblerubbery cover member forming with the supporting member a housing forthe work, said cover member being provided with an inturnednange aroundits periphery dening an opening of smaller dimensions than saidsupporting member and forming a deep, endless groove between saidcovermember and said flange into which the marginal portions of thesupporting member are inserted to effect the closing of the containerabout the work, said flange being suiiiciently flexible to permit saidsupportingmembertobeinsertedinandremoved from said cover member, throughsaid opening.

4. A device constituting the cover section of a separable two-sectioncontainer for a piece of work to be subjected to the pressure of a fluidsurrounding the container, consisting of a ilexible rubbery memberprovided with a marginal portion formed of two layers of rubberymaterial joined at their outer edges to form a deep continuous groove,the inner edges of one of said layers denning an opening through whichthe cooperating section is inserted to dispose its edges in said grooveand through which said cooperating section can be removed, said marginalportion being thin enough to yield under the aforesaid pressure andcause said layers on opposite sides of the groove to be pressed intosealing engagement with the edges of said cooperating section. y

5. A molding blanket of flexible rubbery material for molding assembliesof wood or the like material against the surface of a rigid die, theblanket comprising a central portion adapted to overlie the assembly anda marginal portion surrounding said central portion and integraltherewith, the marginal portion being turned back upon itself to providean inwardly extending continuous groove adapted to be sprung over andsnugly fit the rim of the die to form a seal therewith, the edge of thefolded back portion defining an aperture through which the rim of thedie may be inserted.

6. A device for fabricating an assembly of molded wood or the likematerial comprising, a rigid die member and ablanket of flexible rubberymaterial therefor, the die member comprising a central portion providinga forming surface and a marginal die portion surrounding said centraldie portion and integral therewith, the blanket comprising a centralblanket portion adapted to overlie an assembly on the central portion ofthe die and a marginal blanket portion surrounding said central blanketportion and integral therewith, the marginal blanket portion beingturned back upon itself to provide an inwardly extending continuousgroove adapted to be sprung over and snugly fit the rim of the die toform a seal therewith, the edge of the folded back portion defining anopening through which the rim of the die may be inserted, the

peripheral length of said edge being less than the peripheral length ofthe rim ofthe RAYMOND L. '1 -1 die.

